#include <stdio.h>

void swap(int * a, int* b)
{
	int t;

	t = *a;
	*a = *b;
	*b = t;
}

int main(void)
{
	int a,b;
	
	printf("please input a and b:");
	scanf("%d%d",&a,&b);

	printf("a, b: %d, %d\n",a,b);
	swap(&a,&b);
	printf("a, b: %d, %d\n",a,b);

	return 0;
}
